BP is ready to pay all legitimate claims tied to the oil spill caused by the accident at its Gulf of Mexico undersea well, Chief Executive Tony Hayward told US National Public Radio today.

"We've made it clear that where legitimate claims are made, we will be good for them," Hayward said.

"We have the claims process set up, small claims today that are being paid instantly ... bigger claims we clearly have a process to run through," the BP chief executive added.

He said the London-based company fully accepted responsibility for the spill and would pay for the cleanup operation.

The huge slick caused by the spill is heading for the US Gulf shore in what President Barack Obama has called a "massive and potentially unprecedented environmental disaster".

BP has not put an estimate on the likely costs of the spill, which follows the explosion and sinking of a drilling rig operated by Swiss-based driller Transocean last month.

BP said last week that it and its partners in the well, including Anadarko Petroleum, were paying $6 million (£3.94 million) a day in clean-up efforts but admitted costs would rise sharply when the oil slick hit land, as would claims for damages.

Hayward said the technical options his company was working on to try to seal the ruptured well included an undersea containment system that would capture the leaking oil and channel it to a tanker on the surface.

"It's fabricated and will be on location next weekend," he said.

Another option, the drilling of a relief well to intersect and try to control the ruptured well, was also "now underway," Hayward added.

BP was also using undersea robotic vehicles to try to fix the well blowout preventer - a mechanism that he said had failed to prevent the oil gushing from the ruptured well following the rig accident.

"No one understands why it's failed. We have assembled in Houston 160 companies from across the industry to focus on this task," Hayward said.